MAGNESIUM-SULFATE TOCOLYSIS AND RISK OF NEONATAL DEATH

OBJECTIVE: Our purpose was to evaluate the association between in uter o exposure to magnesium sulfate and neonatal death. STUDY DESIGN: Case -control comparison was performed of singleton infants who died at 0 t o 28 days and control infants who survived to age 3 years and did not have disabling cerebral palsy. All subjects were born between 1983 and 1985 to mothers resident in one of four northern California counties. RESULTS: Magnesium sulfate tocolysis was associated with a decreased risk of neonatal mortality (odds ratio 0.25, 95% confidence interval 0 .6 to 1.1). Adjustment for birth weight and gestational age increased the inverse association (odds ratio 0.09, 95% confidence interval 0.01 to 0.93). The association between neonatal mortality and magnesium su lfate was not altered by maternal infection, gender, maternal race or ethnicity, maternal age, level of care, breech presentation, surgical delivery, corticosteroids, abruptio placentae, placenta previa, or ble eding on admission. CONCLUSIONS: Magnesium sulfate tocolysis was not a ssociated with increased neonatal mortality in premature infants. Thus any association of magnesium with reduced long-term neurologic morbid ity is unlikely to be the result of selective mortality of vulnerable infants.